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51.
52.
Background
There is demand from women for alternatives to giving birth in a standard hospital setting however access to these services is limited. This systematic review examines the literature relating to the economic evaluations of birth setting for women at low risk of complications.Methods
Searches of the literature to identify economic evaluations of different birth settings of the following electronic databases: MEDLINE, CINAHL, EconLit, Business Source Complete and Maternity and Infant care. Relevant English language publications were chosen using keywords and MeSH terms between 1995 and 2015. Inclusion criteria included studies focussing on the comparison of birth setting. Data were extracted with respect to study design, perspective, PICO principles, and resource use and cost data.Results
Eleven studies were included from Australia, Canada, the Netherlands, Norway, the USA, and the UK. Four studies compared costs between homebirth and the hospital setting and the remaining seven focussed on the cost of birth centre care and the hospital setting. Six studies used a cost-effectiveness analysis and the remaining five studies used cost analysis and cost comparison methods. Eight of the 11 studies found a cost saving in the alternative settings. Two found no difference in the cost of the alternative settings and one found an increase in birth centre care.Conclusions
There are few studies that compare the cost of birth setting. The variation in the results may be attributable to the cost data collection processes, difference in health systems and differences in which costs were included. A better understanding of the cost of birth setting is needed to inform policy makers and service providers. 相似文献53.
54.
Chronic non-specific respiratory disease was found by a survey at Chilliwack, B.C., to affect 29.3% of men and 18.0% of women between the ages of 25 and 74. The habit of current cigarette smoking was found to be the most important single factor associated with respiratory disease, and was found to be related to changes in simple measures of lung function. The authors were unable to confirm the existence of a threshold in lifetime cigarette smoking before respiratory disease occurred.Comparisons were made with a population previously studied at Berlin, New Hampshire, U.S.A., in 1961. At Berlin, where pollution by SO2 and dust-fall had been thoroughly documented, the comparable prevalence rates for respiratory disease were 40.0% for men and 21.6% for women. When differences between the two populations as to age and number of cigarettes smoked daily were taken into account, the disease rates in these two communities were found to be quite similar. The Chilliwack sample did, however, have significantly higher values for the lung function tests. 相似文献
55.
Natalia Soriano-Sarabia Nancie M. Archin Rosalie Bateson Noelle P. Dahl Amanda M. Crooks JoAnn D. Kuruc Carolina Garrido David M. Margolis 《PLoS pathogens》2015,11(10)
Eradication of HIV infection will require the identification of all cellular reservoirs that harbor latent infection. Despite low or lack of CD4 receptor expression on Vδ2 T cells, infection of these cells has previously been reported. We found that upregulation of the CD4 receptor may render primary Vδ2 cells target for HIV infection in vitro and we propose that HIV-induced immune activation may allow infection of γδ T cells in vivo. We assessed the presence of latent HIV infection by measurements of DNA and outgrowth assays within Vδ2 cells in 18 aviremic patients on long-standing antiretroviral therapy. In 14 patients we recovered latent but replication-competent HIV from highly purified Vδ2 cells demonstrating that peripheral Vδ2 T cells are a previously unrecognized reservoir in which latent HIV infection is unexpectedly frequent. 相似文献
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57.
Kristie L. Ebi Rosalie Woodruff Alexander von Hildebrand Carlos Corvalan 《EcoHealth》2007,4(3):264-270
Our goal was to identify the climate change-related health risks and vulnerable populations specific to the mountainous regions
of the Hindu Kush–Himalayas. We reviewed published information of the likely health consequences of climate change in mountain
regions, especially the findings of a workshop for countries in the Hindu Kush–Himalaya region, organized by the World Health
Organization, World Meteorological Organization, United Nations Environment Programme, and United Nations Development Programme.
The main climate-related risks in the Hindu Kush–Himalaya region include the expansion of vector-borne diseases as pathogens
take advantage of new habitats in altitudes that were formerly unsuitable. Diarrheal diseases could become more prevalent
with changes in freshwater quality and availability. More extreme rainfall events are likely to increase the number of floods
and landslides with consequent death and injuries. A unique risk is sudden floods from high glacier lakes, which cause substantial
destruction and loss of life. Because glaciers are the main source of freshwater for upland regions and downstream countries,
the long-term reduction in annual glacier snowmelt is expected to heighten existing water insecurity in these areas. Climate
change also is bringing some benefits to mountain populations, including milder winters and longer growing seasons. Populations
in mountain regions have unique combinations of vulnerabilities to climate change. The extent of the health impacts experienced
will depend on the effectiveness of public health efforts to identify and implement low-cost preparedness and response measures,
and on the speed at which emissions of greenhouse gas emissions can be reduced. 相似文献
58.
Frederiksen R Boyer NP Nickle B Chakrabarti KS Koutalos Y Crouch RK Oprian D Cornwall MC 《The Journal of general physiology》2012,139(6):493-505
We report experiments designed to test the hypothesis that the aqueous solubility of 11-cis-retinoids plays a significant role in the rate of visual pigment regeneration. Therefore, we have compared the aqueous solubility and the partition coefficients in photoreceptor membranes of native 11-cis-retinal and an analogue retinoid, 11-cis 4-OH retinal, which has a significantly higher solubility in aqueous medium. We have then correlated these parameters with the rates of pigment regeneration and sensitivity recovery that are observed when bleached intact salamander rod photoreceptors are treated with physiological solutions containing these retinoids. We report the following results: (a) 11-cis 4-OH retinal is more soluble in aqueous buffer than 11-cis-retinal. (b) Both 11-cis-retinal and 11-cis 4-OH retinal have extremely high partition coefficients in photoreceptor membranes, though the partition coefficient of 11-cis-retinal is roughly 50-fold greater than that of 11-cis 4-OH retinal. (c) Intact bleached isolated rods treated with solutions containing equimolar amounts of 11-cis-retinal or 11-cis 4-OH retinal form functional visual pigments that promote full recovery of dark current, sensitivity, and response kinetics. However, rods treated with 11-cis 4-OH retinal regenerated on average fivefold faster than rods treated with 11-cis-retinal. (d) Pigment regeneration from recombinant and wild-type opsin in solution is slower when treated with 11-cis 4-OH retinal than with 11-cis-retinal. Based on these observations, we propose a model in which aqueous solubility of cis-retinoids within the photoreceptor cytosol can place a limit on the rate of visual pigment regeneration in vertebrate photoreceptors. We conclude that the cytosolic gap between the plasma membrane and the disk membranes presents a bottleneck for retinoid flux that results in slowed pigment regeneration and dark adaptation in rod photoreceptors. 相似文献
59.
Boon EM Davis JH Tran R Karow DS Huang SH Pan D Miazgowicz MM Mathies RA Marletta MA 《The Journal of biological chemistry》2006,281(31):21892-21902
The heme cofactor in soluble guanylate cyclase (sGC) is a selective receptor for NO, an important signaling molecule in eukaryotes. The sGC heme domain has been localized to the N-terminal 194 amino acids of the beta1 subunit of sGC and is a member of a family of conserved hemoproteins, called the H-NOX family (Heme-Nitric Oxide and/or OXygen-binding domain). Three new members of this family have now been cloned and characterized, two proteins from Legionella pneumophila (L1 H-NOX and L2 H-NOX) and one from Nostoc punctiforme (Np H-NOX). Like sGC, L1 H-NOX forms a 5-coordinate Fe(II)-NO complex. However, both L2 H-NOX and Np H-NOX form temperature-dependent mixtures of 5- and 6-coordinate Fe(II)-NO complexes; at low temperature, they are primarily 6-coordinate, and at high temperature, the equilibrium is shifted toward a 5-coordinate geometry. This equilibrium is fully reversible with temperature in the absence of free NO. This process is analyzed in terms of a thermally labile proximal Fe(II)-His bond and suggests that in both the 5- and 6-coordinate Fe(II)-NO complexes of L2 H-NOX and Np H-NOX, NO is bound in the distal heme pocket of the H-NOX fold. NO dissociation kinetics for L1 H-NOX and L2 H-NOX have been determined and support a model in which NO dissociates from the distal side of the heme in both 5- and 6-coordinate complexes. 相似文献
60.
Protein phosphatase 2A regulatory subunit B56alpha associates with c-myc and negatively regulates c-myc accumulation 总被引:1,自引:0,他引:1
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Protein phosphatase 2A (PP2A) plays a prominent role in controlling accumulation of the proto-oncoprotein c-Myc. PP2A mediates its effects on c-Myc by dephosphorylating a conserved residue that normally stabilizes c-Myc, and in this way, PP2A enhances c-Myc ubiquitin-mediated degradation. Stringent regulation of c-Myc levels is essential for normal cell function, as c-Myc overexpression can lead to cell transformation. Conversely, PP2A has tumor suppressor activity. Uncovering relevant PP2A holoenzymes for a particular target has been limited by the fact that cellular PP2A represents a large heterogeneous population of trimeric holoenzymes, composed of a conserved catalytic subunit and a structural subunit along with a variable regulatory subunit which directs the holoenzyme to a specific target. We now report the identification of a specific PP2A regulatory subunit, B56alpha, that selectively associates with the N terminus of c-Myc. B56alpha directs intact PP2A holoenzymes to c-Myc, resulting in a dramatic reduction in c-Myc levels. Inhibition of PP2A-B56alpha holoenzymes, using small hairpin RNA to knock down B56alpha, results in c-Myc overexpression, elevated levels of c-Myc serine 62 phosphorylation, and increased c-Myc function. These results uncover a new protein involved in regulating c-Myc expression and reveal a critical interconnection between a potent oncoprotein, c-Myc, and a well-documented tumor suppressor, PP2A. 相似文献